I doubt that 'continue' can be used there - what if we have a caseof in a loop?
foreach(x; y)
{
caseof(s[i])
{
case '': continue; // fallthrough or continue the loop?
}
}
One could workaround this by giving the loop a label and using it
with 'continue', but still, this might be confusing for beginners.

I don't like that goto too much... You usually just want do go down (and by

But it's been discussed many times now and it doesn't seem likely Walter's

I agree with Walter when he says it's better that if a syntax that looks like

looks different. Instead of switch{} it may be used caseof{}, plus the
"default"
statement, plus a new statement like "fall" (or something similar) that tells
the compiler just to not break, so it's just the opposite of C :-)

This whole conversation about switch was kind of lost on me, but I have to
contribute this.
I, at various times, have written code that depends on case statements falling
through, while not being identical!
For example:
switch(foo)
{
case 'bob':
//Do bob stuff
//Fall through and doo bar stuff too.
case 'bar':
//Do bar stuff and exit
break;
case 'baz':
//Do some baz stuff
break;
}
Whatever is changed shouldn't break this.

but I have to contribute this.
I, at various times, have written code that depends on case statements falling
through, while not being identical!
For example:
switch(foo)
{
case 'bob':
//Do bob stuff
//Fall through and doo bar stuff too.
case 'bar':
//Do bar stuff and exit
break;
case 'baz':
//Do some baz stuff
break;
}
Whatever is changed shouldn't break this.

Good news for you, then. Nothing's going to change!
But man I wish it would, for 2.0 that is. I've been hit at least
half-a-dozen times in the past year by missing break statements in my D
code. And I have a C++ background! So it's not about familiarity. It
bites me when I'm coding C++ just as frequently. It's simply a C/C++
mis-feature that D failed to correct.
--bb

I, at various times, have written code that depends on case statements falling
through, while not being identical!

If you take a look at my original post, I have suggested to use a "fall" or
"continue" statement when you want to go down, and nothing if you want the
default of going at the end of the switch...
Bye,
bearophile

I, at various times, have written code that depends on case statements falling
through, while not being identical!

If you take a look at my original post, I have suggested to use a "fall" or
"continue" statement when you want to go down, and nothing if you want the
default of going at the end of the switch...
Bye,
bearophile

The same problems you initially mentioned still exist in your proposal. You
just moved them around:
caseof(Foo)
{
case 'foo':
writeflin("bar");
fall;
x = 3;
case 'bar':
writefln("OMGWTF X != 3");
}
Whatever complicated syntax you invent there will be unreachable code. The
compiler should produce ERRORS on any unreachable code.
The error you linked to is not switch-induced, but stupidity induced. However,
I will say this: D is starting to become so complex that it is becoming
difficult to understand the entire specification. Once it is no longer
feasible to have the spec memorized then it becomes easy to make very silly
mistakes.
-S.

I agree (D too has a simple way to spot dead code under a return in not-release
mode).
Sometimes Pascal syntax is better than the C one, the switch is one of them, I
like the Pascal version better.
In the Python community people collect use cases, do a simple frequency count
of them, and then usually look for a simple solution able to cover most of
them. So we can collect some use cases of the switch. I presume most use cases
are covered by a Pascal-like syntax. The other situations are probably covered
by putting commas between alternative cases. What other use cases do you people
have?

The error you linked to is not switch-induced, but stupidity induced.<

Then the language (and language designers) must be twice intelligent to avoid
errors done by "stupid" humans. Technology must adapt itself to the limits of
the human brain, otherwise it's far more stupid than the humans. In this
situation I think such adaptation doesn't require a more complex syntax or the
usage or more CPU or more memory. A change has the disadvantage that it makes D
syntax looking a bit less like C, and this may be a disadvantage.

However, I will say this: D is starting to become so complex that it is
becoming difficult to understand the entire specification. Once it is no
longer feasible to have the spec memorized then it becomes easy to make very
silly mistakes.<

I too like simpler languages better, that's why I like Python and D (D is
simpler than C++ still) :-)
D has many parts, so it's more complex than a language with less parts, but
usually each D part has few interactions with all the other parts, so the
actual complexity isn't too much high :-)
Bye,
bearophile

In the Python community people collect use cases, do a simple frequency
count of them, and then usually look for a simple solution able to
cover most of them. So we can collect some use cases of the switch. I
presume most use cases are covered by a Pascal-like syntax. The other
situations are probably covered by putting commas between alternative
cases. What other use cases do you people have?

In the Python community people collect use cases, do a simple
frequency count of them, and then usually look for a simple solution
able to cover most of them. So we can collect some use cases of the
switch. I presume most use cases are covered by a Pascal-like syntax.
The other situations are probably covered by putting commas between
alternative cases. What other use cases do you people have?

A use case?
I quite fancy GCC's extension which allows you to put ranges in case
statements, for instance:
switch (myChar) {
case 'a'...'z':
case 'A'...'Z':
case '0'...'9':
// do something.
}
I think D should have it too. (Also, since we're at it, it's covered by
Pascal.)

In D parance, that would mean 'A' to 'Y' inclusive, but excluding 'Z'.
(The three dot form could be used to mean "inclusive" though)

Not only;
it would violate the 0..length meaning, and he also failed to recognize the
syntax we've been pushing for to distinguish the new switch from the old.
The new one looks like this:
switch(x) {
case(y) {
}
case (z) {
}
case (a) {
}
}
Why?
1) It's more consistent with other structured D statements.
2) It differentiates it from the old way in our minds
3) It allows us to support both ways for a transition period.
4) The {} is syntactically associated with only affecting what's inside, while
: is used to mean "everything after here" which is semantically correct.
Regards,
Dan

In the Python community people collect use cases, do a simple
frequency count of them, and then usually look for a simple solution
able to cover most of them. So we can collect some use cases of the
switch. I presume most use cases are covered by a Pascal-like syntax.
The other situations are probably covered by putting commas between
alternative cases. What other use cases do you people have?

A use case?
I quite fancy GCC's extension which allows you to put ranges in case
statements, for instance:
switch (myChar) {
case 'a'...'z':
case 'A'...'Z':
case '0'...'9':
// do something.
}
I think D should have it too. (Also, since we're at it, it's covered by
Pascal.)

This whole conversation about switch was kind of lost on me, but I have
to contribute this.
I, at various times, have written code that depends on case statements
falling through, while not being identical!
For example:
switch(foo)
{
case 'bob':
//Do bob stuff
//Fall through and doo bar stuff too.
case 'bar':
//Do bar stuff and exit
break;
case 'baz':
//Do some baz stuff
break;
}
Whatever is changed shouldn't break this.

This whole conversation boggles me. cases should *never* fall through its
dangerous.

In other news, it has been discovered that the risk of choking is greatly
increased by eating anything that is not pureed. As a result, lawmakers have
outlawed solid food.
Programming requires a brain.
You should go read DailyWTF for awhile. It is possible to do the most
ridiculous things no matter how carefully the language is crafted. We should
just stay away from hand-holding and focus on making things easier.
I agree with measures that make debugging easier when dealing with naming and
hijacking. However, a simple step-through will reveal a case falling through
when it shouldn't. The aforementioned issues are not as easily caught.
-S.

Well one probably not. For one, there isn't a formal definition given for that
term on your cited page.
Secondly, my point is that most things that are generic enough to be useful,
are inherently dangerous if misused. Consider most kitchen utensils. The
ones that are "safe" only do one thing, and if you want a "safe" kitchen then
you need hundreds of these gadgets.
goto, and break, are defined in such general terms that they are useful over a
wide range of constructs. If you want to make things "safe" you need to
pollute your "kitchen" with gadgets.
I would like to see the specification stay simple enough that know what exactly
each "tool" does in a general sense and then apply it in a specific way. Now
sometimes, if something is used enough, then it makes sense to have a special
tool for it. (Like having a coffee pot instead of just boiling grounds and
straining them out later.) This is why I like D instead of just straight up C.

Programming requires a brain.

development.
Fall through unnecessarily complicates things without adding much if
indeed any power.
I'd rather use my brain on the important things.

And calling into another function in order to duplicate functionality requires
introduce a new scope....
If the specification is easily understood then there isn't much problem here...

You should go read DailyWTF for awhile. It is possible to do the most
ridiculous things no matter how carefully the language is crafted. We
should just stay away from hand-holding and focus on making things
easier.

easier
to write safe code?

It should be easier to write safe code, and easier to debug and easier to read.
Sometimes though, the compiler should just warn you when you're using a
construct incorrectly. For example, a return statement can cause unreachable
code. Should we get rid of the return statement in favor of 15 different
keywords to do similar (but specific) things, or make it an error when it
produces unreachable code?
I think my take on how I run my kitchen is applicable to D.

I agree with measures that make debugging easier when dealing with
naming and hijacking. However, a simple step-through will reveal a case
falling through when it shouldn't. The aforementioned issues are not as
easily caught.

easy enough to
find the source and targets of a goto with a find in your code. Okay its
nowhere near
in the same league as goto but the point's still valid.

By aforementioned issues I meant hijacking and protection levels. Which are
basically the same reason we require our variables to be defined instead of
just implying them when they're used.
Is the trade off of having to declare your variables worth not having to figure
out what is going on when you mistype a variable name? Yes, most certainly.
I don't think switch, goto, break, and the like are anything like that.
-S.

However, a simple step-through will reveal a case falling through when it
shouldn't.

Eliminating the possibility of unintentional fall-through altogether
will eliminate the need for even your "simple step-through".
And simple step through may not be so simple when the program is
hundreds of thousands of lines long. Mistaken fall-through in some
switch in some function in some module can change a state, and that
state can later trigger another different change of state and so on,
until finally somewhere your program crashes because of an incorrect
state a dozen causal steps away from the original problem.
So "simple step through" may mean "simply" stepping through thousands of
lines of code to try to figure out where things first went wrong. It
can be very non-trivial.
Implicit switch fall-through is evil.
--bb